Perhaps you should try some spelling variations:
"a robert j. german book" » "a robert j. german books", "a robert j. german food", "3 robert j. german book", "a robust j. german book", "a robot j. german book", "a robert _. german book", "a robert e. german book"
"dr robert j. german book" » "dr robert j. german books", "dr robert j. german food", "dr robert _. german book", "dr robert e. german book"
"a robert j. heilman ebooks" » "3 robert j. heilman ebooks", "a robust j. heilman ebooks", "a robot j. heilman ebooks", "a robert _. heilman ebooks", "a robert e. heilman ebooks", "a robert j. heilmann ebooks", "a robert j. hellman ebooks", "a robert j. helman ebooks", "a robert j. heilman books", "a robert j. heilman ebook", "a robert j. heilman redbooks"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("a robert j. german book") OR ("dr robert j. german book"))) or ("a robert j. heilman ebooks"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("a robert j. german book") OR ("dr robert j. german book"))) OR ("a robert j. heilman ebooks")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"a robert j. german book\") OR (\"dr robert j. german book\"))) or (\"a robert j. heilman ebooks\"))".
• Removing quotes may allow a broader search: (((( a robert j. german book ) OR ( dr robert j. german book ))) or ( a robert j. heilman ebooks )).
• Adding a wildcard symbol may retrieve word variants: (((("a robert j. german book") OR ("dr robert j. german book"))) or ("a robert j. heilman ebooks"))*.